Terminal device, base station device, and method

ABSTRACT

A terminal device including a control unit that transmits first resource information, which indicates a radio resource available to another communication device among radio resources of which access rights are acquired by performing carrier sense, on an uplink or a sidelink.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 16/959,749, filed on Jul. 2, 2020, which is a U.S.National Phase of International Patent Application No. PCT/JP2018/040170filed on Oct. 29, 2018, which claims priority benefit of Japanese PatentApplication No. JP 2018-002388 filed in the Japan Patent Office on Jan.11, 2018. Each of the above-referenced applications is herebyincorporated herein by reference in its entirety.

FIELD

The present disclosure relates to a terminal device, a base stationdevice, and a method.

BACKGROUND

Wireless access schemes and wireless networks of cellular mobilecommunication (hereinafter also referred to as long term evolution(LTE), LTE-advanced (LTE-A), LTE-advanced pro (LTE-A Pro), new radio(NR), new radio access technology (NRAT), 5G, evolved universalterrestrial radio access (EUTRA), or further EUTRA (FEUTRA)) are underreview in 3rd generation partnership project (3GPP). Incidentally, inthe following description, LTE includes LTE-A, LTE-A Pro, and EUTRA, andNR includes NRAT, and FEUTRA. In LTE, a base station device (basestation) is also referred to as evolved NodeB (eNodeB), and in NR, thebase station device (base station) is also referred to as gNodeB (gNB).In LTE and NR, a terminal device (a mobile station, a mobile stationdevice, and a terminal) is also referred to as user equipment (UE). LTEand NR are cellular communication systems in which a plurality of areascovered by base station devices is arranged in a cell shape. A singlebase station device may manage a plurality of cells.

NR is a wireless access scheme of the next generation of LTE and is adifferent radio access technology (RAT) from LTE. NR is an accesstechnology that can support various use cases including enhanced mobilebroadband (eMBB), massive machine type communications (mMTC), and Ultrareliable and low latency communications (URLLC). NR is examined for atechnical framework that addresses usage scenarios, requirements, anddeployment scenarios in those use cases.

In an unlicensed band and a license shared band, the operation of awireless access scheme based on cellular communication is beingexamined. In such an unlicensed band, coexistence with other nodes andwireless systems is considered important, and in a wireless accessscheme such as LTE and NR, functions such as listen before talk (LBT)for performing channel sensing before transmission and discontinuoustransmission are required. Details of a wireless access scheme based onNR in the unlicensed band are disclosed in Non Patent Literature 1.Incidentally, the unlicensed band is, for example, a 2.4 GHz band, a 5GHz band, and a 6 GHz band. The license sharing band is, for example, a3.5 GHz band or a 37 GHz band.

CITATION LIST Non Patent Literature

-   Non Patent Literature 1: RP-172021, “Study on NR-based Access to    Unlicensed Spectrum”, 3GPP TSG RAN Meeting #77, Sapporo, Japan, Sep.    11-14, 2017.

SUMMARY Technical Problem

However, in a case where each communication device independentlyperforms LBT in an environment where a plurality of communicationdevices exists, the use efficiency of radio resources (a frequencyresource and a time resource) may be reduced. This is because a waitingtime due to sensing for acquiring an access right occurs each time eachcommunication device uses the radio resources.

In this regard, the present disclosure provides a mechanism that enablesa plurality of communication devices to use radio resources moreefficiently.

Solution to Problem

According to the disclosure, a terminal device is provided thatincludes: a control unit configured to transmit first resourceinformation, which indicates a radio resource available to anothercommunication device among radio resources of which access rights areacquired by performing carrier sense, on an uplink or a sidelink.

Moreover, according to the disclosure, a base station device is providedthat includes: a control unit configured to receive resource informationwhich indicates, among radio resources of which access rights areacquired by a terminal device by performing carrier sense, a resourceavailable to another communication device other than the terminal devicefrom the terminal device and use the resource available to the anothercommunication device for communication.

Moreover, according to the disclosure, a method performed by aprocessor, the method is provided that includes: transmitting firstresource information, which indicates a radio resource available toanother communication device among radio resources of which accessrights are acquired by performing carrier sense, on an uplink or asidelink.

Advantageous Effects of Invention

As described above, according to the present disclosure, a mechanism isprovided that enables a plurality of communication devices to use radioresources more efficiently. Incidentally, the above effects are notnecessarily limited, and any of the effects described in thisspecification or other effects that can be grasped from thisspecification may be exerted together with or in place of the aboveeffects.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating an example of an overall configurationof a system according to an embodiment of the present disclosure.

FIG. 2 is a diagram for describing an example of communication in LAA.

FIGS. 3A, 3B, and 3C are diagrams illustrating examples of a frameconfiguration of self-contained transmission in this embodiment.

FIG. 4 is a block diagram illustrating an example of a configuration ofa base station device according to this embodiment.

FIG. 5 is a block diagram illustrating an example of a configuration ofa terminal device according to this embodiment.

FIG. 6 is a diagram for describing an example of sharing an access rightaccording to this embodiment.

FIG. 7 is a diagram for describing another example of sharing the accessright according to this embodiment.

FIG. 8 is a diagram for describing still another example of sharing theaccess right according to this embodiment.

FIG. 9 is a diagram for describing still another example of sharing theaccess right according to this embodiment.

FIG. 10 is a diagram for describing sharing of an access right by asecond terminal device according to this embodiment.

FIG. 11 is a flowchart illustrating an example of a flow of an accessright sharing process executed by a first terminal device according tothis embodiment.

FIG. 12 is a flowchart illustrating an example of a flow of an accessright sharing process executed by the base station device according tothis embodiment.

FIG. 13 is a flowchart illustrating an example of a flow of an accessright sharing process executed by the second terminal device accordingto this embodiment.

FIG. 14 is a flowchart illustrating an example of the flow of the accessright sharing process executed by the second terminal device accordingto this embodiment.

FIG. 15 is a block diagram illustrating a first example of a schematicconfiguration of an eNB.

FIG. 16 is a block diagram illustrating a second example of a schematicconfiguration of the eNB.

FIG. 17 is a block diagram illustrating an example of a schematicconfiguration of a smartphone.

FIG. 18 is a block diagram illustrating an example of a schematicconfiguration of a car navigation device.

DESCRIPTION OF EMBODIMENTS

Hereinafter, preferred embodiments of the present disclosure will bedescribed in detail with reference to the accompanying drawings. Inaddition, in this specification and drawing, constituent elements havingsubstantially the same functional configuration are denoted by the samereference numerals, and redundant description is omitted.

The description will be made in the following order.

-   -   1. Introduction    -   1.1. System configuration example    -   1.2. Technical issues    -   1.3. Overview of proposed method    -   1.4. Related technologies    -   2. Configuration example    -   2.1. Configuration example of base station device    -   2.2. Configuration example of terminal device    -   3. Technical features    -   3.1. Sharing of sharable resource information    -   3.2. Sharing access rights    -   3.3. Contents of sharable resource information    -   3.4. Transmission method of sharable resource information    -   3.5. Sharing by second terminal device    -   3.6. Flow of processing    -   4. Application example    -   5. Conclusion

1. Introduction <1.1. System Configuration Example>

FIG. 1 is a diagram illustrating an example of an overall configurationof a system 1 according to an embodiment of the present disclosure. Asillustrated in FIG. 1 , the system 1 includes a base station device 100(100A and 100B), a terminal device 200 (200A and 200B), a core network20, and a packet data network (PDN) 30.

The base station device 100 operates a cell 11 (11A or 11B) and providesa wireless service to one or more terminal devices located inside thecell 11. For example, the base station device 100A provides a wirelessservice to the terminal device 200A, and the base station device 100Bprovides a wireless service to the terminal device 200B. The cell 11 canbe operated according to any wireless communication system such as LTEor new radio (NR). The base station device 100 is connected to the corenetwork 20. The core network 20 is connected to the PDN 30.

The core network 20 may include a mobility management entity (MME), aserving gateway (S-GW), a PDN gateway (P-GW), a policy and charging rulefunction (PCRF), and a home subscriber server (HSS). Alternatively, thecore network 20 may include entities of the NR having functions similarto those described above. The MME is a control node that handles asignal of a control plane, and manages the moving state of the terminaldevice. The S-GW is a control node that handles a signal of a userplane, and is a gateway device that switches a transfer path of userdata. The P-GW is a control node that handles the signal of the userplane, and is a gateway device serving as a connection point between thecore network 20 and the PDN 30. The PCRF is a control node that controlsa policy such as quality of service (QoS) for the bearer and charging.The HSS is a control node that handles subscriber data and performsservice control.

The terminal device 200 wirelessly communicates with the base stationdevice 100 on the basis of the control by the base station device 100.The terminal device 200 may be a so-called user equipment (UE). Forexample, the terminal device 200 transmits an uplink signal to the basestation device 100 and receives a downlink signal from the base stationdevice 100. The terminal device 200 can also perform device-to-device(D2D) communication. That is, the terminal device 200 can transmit asidelink signal of another terminal device 200 and receive a sidelinksignal from the another terminal device 200.

<1.2. Technical Issues>

Case where base station device acquires access right

Conventionally, in licensed assisted access (LAA), the base stationdevice acquires an access right to a radio resource (hereinafter, alsoreferred to as a channel). Then, the acquired access right is shared bythe base station device and the terminal device communicating with thebase station device. This point will be described with reference to FIG.2 .

FIG. 2 is a diagram for describing an example of communication in LAA.The upper part of FIG. 2 illustrates carrier sense performed by the basestation device and a signal transmitted by the base station device. Thelower part of FIG. 2 illustrates carrier sense performed by the terminaldevice and a signal transmitted by the terminal device. The rectangledescribed as DL is a time resource for transmitting a downlink signal.The time resource is, for example, a slot or a sub frame. The rectangledescribed as UL is a time resource for transmitting a downlink signal.As illustrated in FIG. 2 , the base station device first performscarrier sense using random back-off, and acquires an access right. Next,on the basis of the acquired access right, the base station devicetransmits a downlink signal within a period in which the channel may beoccupied (channel occupancy time: COT). The COT is the period duringwhich the acquired access right is valid. On the other hand, the basestation device instructs the terminal device to perform uplinktransmission during the COT by using an uplink grant. Then, afterperforming carrier sense without using random back-off, the terminaldevice transmits an uplink signal according to the uplink grant.

A channel access method changes depending on whether or not it is withinthe COT. Specifically, a communication device performs carrier sense byusing random back-off and accesses a channel outside the COT (forexample, LBT category 4). On the other hand, the communication deviceperforms carrier sense without using random back-off within the COT,that is, during a period in which the communication device has an accessright, and accesses a channel (for example, LBT category 2). In theexample illustrated in FIG. 2 , the base station device does not acquirethe access right at first (that is, is outside the COT), and thusaccesses the channel by using random back-off. On the other hand, on thebasis of the uplink grant, the terminal device shares the access rightacquired by the base station device and accesses the channel withoutusing random back-off during a period in which the access right acquiredby the base station device is valid (that is, within the COT). Asdescribed above, in the uplink transmission in the LAA, the terminaldevice does not have to perform the channel access using the randomback-off from 1 by sharing the access right.

Various Examination

On the other hand, in LTE and NR, uplink grant-free transmission (alsoreferred to as grantless transmission) is being examined. The grant-freetransmission is a method in which the terminal device transmits theuplink signal without receiving the uplink grant from the base stationdevice in a periodic resource semi-statically indicated by radioresource control (RRC) signaling.

In NR, autonomous uplink channel access in which the terminal deviceacquires an access right is being examined. The autonomous uplinkchannel access is a method in which, when performing uplink grant-freetransmission, the terminal device itself performs LBT using a channelaccess procedure using random back-off to acquire an access right.

The D2D communication using an unlicensed band is being examined. Thereis a merit that D2D communication between different operators becomeseasier to use by using the unlicensed band for D2D communication.

Technical Issues

Simply acquiring an access right by each terminal device independentlymay reduce the use efficiency of radio resources. This is because evenif the terminal device acquires an access right, there is no mechanismfor sharing the acquired access right with another communication device.Therefore, after acquiring an access right, the terminal device oncereleases the channel for communication by another communication device.Then, the another communication device performs channel access usingrandom back-off from 1, so that a waiting time occurs.

<1.3. Overview of Proposed Method>

Therefore, in one embodiment of the present disclosure, in view of thetechnical problem described above, a mechanism is propose in which theaccess right acquired by the terminal device 200 can be shared byanother communication device (for example, the base station device 100or another terminal device 200).

In this embodiment, first, the terminal device 200 acquires an accessright by performing channel access using random back-off. Thereafter,the terminal device 200 transmits information, which indicates the radioresource available to another communication device among the radioresources of which the access rights are acquired, on the uplink or thesidelink. Accordingly, the another communication device that receivesuch information can perform communication by sharing the access rightacquired by the terminal device 200 without acquiring an access right byitself. Specifically, the another communication device performscommunication by performing channel access without using random back-offin the radio resource related to the access right acquired by theterminal device 200. The another communication devices can performcommunication without acquiring the access right, so that the processingload is reduced. In addition, since the carrier sense using the randomback-off is not performed, the waiting time is reduced, so that the useefficiency of the radio resources can be improved.

<1.4. Related Technologies>

Hereinafter, a technology related to the proposed technique will bedescribed.

<Frame Configuration of NR in this Embodiment>

In NR, a physical channel and/or a physical signal may be transmitted bya self-contained transmission. FIGS. 3A, 3B, and 3C illustrate examplesof a frame configuration of self-contained transmission in thisembodiment. In the self-contained transmission, one transceiving isconfigured in the order of a continuous downlink transmission, a GP, anda continuous downlink transmission from the beginning. The continuousdownlink transmission includes at least one downlink control informationand DMRS. The downlink control information gives an instruction onreception of a downlink physical channel included in the continuousdownlink transmission or transmission of an uplink physical channelincluded in the continuous uplink transmission. In a case where thedownlink control information gives the instruction on reception of thedownlink physical channel, the terminal device 200 attempts to receivethe downlink physical channel on the basis of the downlink controlinformation. Then, the terminal device 200 transmits the receptionsuccess/failure (decoding success/failure) of the downlink physicalchannel by using the uplink control channel included in the uplinktransmission allocated after the GP. On the other hand, in a case wherethe downlink control information gives the instruction on transmissionof the uplink physical channel, the transmitted uplink physical channelis transmitted being included in the uplink transmission on the basis ofthe downlink control information. In this way, by flexibly switchingbetween transmission of uplink data and transmission of downlink dataaccording to the downlink control information, it is possible toimmediately respond to an increase or decrease in the traffic ratiobetween the uplink and the downlink. Further, by providing notificationof the reception success/failure of the downlink by the immediatelyfollowing uplink transmission, it is possible to realize the low-delaycommunication of the downlink.

A unit slot time is a minimum time unit that defines a downlinktransmission, a GP, or an uplink transmission. The unit slot time isreserved for any of the downlink transmission, the GP, or the uplinktransmission. The unit slot time does not include both downlinktransmission and uplink transmission. The unit slot time may be aminimum transmission time of a channel associated with a DMRS includedin the unit slot time. One unit slot time is defined, for example, as anintegral multiple of a sampling interval (T_(s)) of NR and a symbollength.

A unit frame time may be a minimum time specified in the scheduling. Theunit frame time may be a minimum unit at which a transport block istransmitted. The unit slot time may be the maximum transmission time ofa channel associated with the DMRS included in the unit slot time. Theunit frame time may be a unit time for determining uplink transmissionpower in the terminal device 200. The unit frame time may be referred toas a sub frame. There are three types of unit frame time of downlinktransmission only, uplink transmission only, and a combination of uplinktransmission and downlink transmission. One unit frame time is definedby, for example, an integral multiple of a sampling interval (T_(s)) ofNR, a symbol length, and a unit slot time.

A transceiving time is a time of one transceiving. The time between onetransceiving and another transceiving is occupied by a time (gap) duringwhich no physical channel or physical signal is transmitted. Theterminal device 200 does not have to average the CSI measurement betweendifferent transceivings. The transceiving time may be referred to asTTI. One transceiving time is defined by, for example, an integermultiple of a sampling interval (T_(s)) of NR, a symbol length, a unitslot time, and a unit frame time.

<Channel Access Procedure for Unlicensed Channel>

The channel access (Channel access and Listen before Talk) procedure isperformed to access an unlicensed channel for performing transmission bythe base station device or the terminal device.

In the channel access procedure, one or more times of channel sensingare performed. On the basis of the sensing result, it is determined(empty determination) whether the channel is idle (unoccupied,available, enable) or busy (busy, occupied, unavailable, disable). Inchannel sensing, the power of the channel during a predetermined waitingtime is sensed.

Examples of the waiting time of the channel access procedure include afirst waiting time (slot), a second waiting time, a third waiting time(defer period), and a fourth waiting time.

A slot is a unit of waiting time of the base station device and theterminal device in the channel access procedure. A slot is defined by,for example, nine microseconds.

In the second waiting time, one slot is inserted at the head. The secondwaiting time is defined, for example, as 16 microseconds.

The defer period is configured by a second waiting time and a pluralityof consecutive slots following the second waiting time. The number ofconsecutive slots following the second waiting time is determined on thebasis of a priority class (channel access priority class) used tosatisfy QoS.

The fourth waiting time is configured by the second waiting time and oneslot following the second waiting time.

The base station device or the terminal device senses a predeterminedchannel during a predetermined slot period. In a case where the powerdetected by the base station device or the terminal device for at leastfour microseconds within the predetermined slot period is smaller than apredetermined power detection threshold, the predetermined slot isconsidered to be idle. On the other hand, in a case where the power isgreater than a predetermined power detection threshold, thepredetermined slot is considered to be busy.

The channel access procedure includes a first channel access procedureand a second channel access procedure. The first channel accessprocedure is the first channel access procedure is performed using aplurality of slots and defer periods. The second channel accessprocedure is performed using one fourth waiting time.

The parameters related to channel access are determined on the basis ofthe priority class. Examples of the parameters related to channel accessinclude a minimum contention window, a maximum contention window, amaximum channel occupation time, and a value that the contention windowcan take. The priority class is determined by a value of a QoS classidentifier (QCI) that processes quality of service (QoS). Table 1 showsa correspondence table between priority classes and parameters relatedto channel access, and Table 2 shows an example of mapping betweenpriority classes and QCIs.

TABLE 1 one example of correspondence table between priority class andparameters related to channel access Channel Minimum Maximum Maximumaccess contention contention channel Possible value of priority windowwindow occupation contention window class (p) m_(p) CW_(min, p)CW_(max, p) time T_(mcot, p) CW_(P) 1 1 3 7 2 ms {3, 7}  2 1 7 15 3 ms{7, 15} 3 3 15 63 8 or 10 ms {15, 31, 63} 4 7 15 1023 8 or 10 ms {15,31, 63, 127, 255, 511, 1023}

TABLE 2 One example of mapping between priority class and QCI Channelaccess priority class QCI 1 1, 3, 5, 65, 66, 69, 2 2, 7 3 4, 6, 8, 9 4Other than above

<Details of First Channel Access Procedure>

In the first channel access procedure, the following procedure isperformed.

(0) Channel sensing is performed during the defer period. In a casewhere the channel is idle in the slot within the defer period, theprocess proceeds to Step (1), and otherwise, the process proceeds toStep (6).

(1) The initial value of a counter is obtained. The possible value ofthe initial value of the counter is an integer between zero and acontention window CW. The initial value of the counter is determinedrandomly according to a uniform distribution. The initial value of thecounter is set in a counter N, and the process proceeds to the Step (2).

(2) In a case where the counter N is larger than zero and the counter Nis selected to be subtracted, one is subtracted from the counter N.Thereafter, the process proceeds to the Step (3).

(3) A slot period is added to waiting. Further, in the additional slot,the channel is sensed. In a case where the additional slot is idle, theprocess proceeds to Step (4), and otherwise, the process proceeds toStep (5).

(4) In a case where the counter N is zero, this procedure is stopped.Otherwise, the process proceeds to Step (2).

(5) A defer period is added to waiting. Further, the channel is senseduntil any one of the slots included in the additional defer period isdetected as busy, or until all the slots included in the additionaldefer period can be detected as idle. Thereafter, the process proceedsto the Step (6).

(6) In a case where the channel is sensed as idle in all the slotsincluded in the additional defer period, the process proceeds to Step(4), and otherwise, the process proceeds to Step (5).

After the stop of the Step (4) in the above procedure, transmissionincluding data such as PDSCH and PUSCH is performed on the channel.

Incidentally, after the stop of the Step (4) in the above procedure,transmission may not be performed on the channel. In this case,thereafter, in a case where the channel is idle immediately beforetransmission in all the slots and the defer period, transmission may beperformed without performing the above procedure. On the other hand, ina case where the channel is not idle in any of the slots and the deferperiod, the channel was sensed as idle in all of the slots in theadditional defer period, and then the process proceeds to Step (1) inthe above procedure.

<Details of Second Channel Access Procedure>

In the second channel access procedure, the transmission may occurimmediately after the channel is considered to be idle as a result ofsensing of at least the fourth waiting time. On the other hand, in acase where the channel is considered not to be idle as a result ofsensing of at least the fourth waiting time, transmission is notperformed.

<Contention Window Adaptation Procedure>

The contention window (CW) used in the first channel access procedure isdetermined on the basis of the contention window adaptation procedure.

The value of the contention window CW is held for each priority class.The contention window CW takes a value between the minimum contentionwindow and the maximum contention window. The minimum contention windowand the maximum contention window are determined on the basis of thepriority class.

The adjustment of the value of the contention window CW is performedbefore Step (1) of the first channel access procedure. In a case wherethe proportion of NACK in the HARQ response corresponding to the sharedchannel of at least the reference sub frame or reference HARQ process inthe contention window adaptation procedure is higher than a threshold,the value of the contention window CW is increased, and otherwise, thevalue of the contention window CW is set to the minimum contentionwindow.

The value of the contention window CW is increased on the basis of, forexample, the equation CW=2×(CW+1)−1.

<Details of Channel Access Procedure in Downlink>

In a case where downlink transmission including PDSCH, PDCCH, and/orEPDCCH is performed on the unlicensed channel, the base station deviceaccesses the channel on the basis of the first channel access procedureand performs the downlink transmission.

On the other hand, in a case where downlink transmission that includesthe DRS but does not include the PDSCH is performed in the unlicensedchannel, the base station device accesses the channel on the basis ofthe second channel access procedure and performs the downlinktransmission. Note that the period of the downlink transmission ispreferably smaller than one millisecond.

<Details of Channel Access Procedure in Uplink>

In a case where an instruction to perform the first channel accessprocedure in the uplink grant for scheduling the PUSCH is given in theunlicensed channel, the terminal device performs the first channelaccess procedure before the uplink transmission including the PUSCH.

In a case where an instruction to perform the second channel accessprocedure is given in the uplink grant for scheduling the PUSCH, theterminal device performs the second channel access procedure before theuplink transmission including the PUSCH.

For uplink transmissions which does not include the PUSCH but includesthe SRS, the terminal device performs the second channel accessprocedure before the uplink transmission.

In a case where the end of the uplink transmission indicated by theuplink grant is within the uplink period (UL duration), regardless ofthe procedure type indicated by the uplink grant, the terminal devicetransmits the second channel access procedure before the uplinktransmission.

In a case where uplink transmission continues with the fourth waitingtime interposed after the end of downlink transmission from the basestation, the terminal device performs the second channel accessprocedure before the uplink transmission.

<Channel Access Procedure of NR in this Embodiment>

In the channel access procedure in the unlicensed channel using NR,non-beamformed channel sensing and beamformed channel sensing areperformed.

The non-beamformed channel sensing is channel sensing by reception inwhich directivity is not controlled, or channel sensing withoutdirection information. The channel sensing without direction informationis, for example, channel sensing in which measurement results areaveraged in all directions. The transmitting station does not need torecognize the directivity (angle and direction) used in the channelsensing.

The beamformed channel sensing is channel sensing by reception in whichdirectivity is controlled, or channel sensing with directioninformation. That is, the beamformed channel sensing is channel sensingin which the reception beam is directed in a predetermined direction. Atransmitting station having a function of performing beamformed channelsensing can perform one or more times of channel sensing using differentdirectivities.

By performing beamformed channel sensing, the area detected by sensingis reduced. Accordingly, the transmitting station can reduce thefrequency of detecting a communication link that does not causeinterference and can reduce the problem of the terminals.

2. Configuration Example <2.1. Configuration Example of Base StationDevice>

FIG. 4 is a block diagram illustrating an example of a configuration ofthe base station device 100 according to this embodiment. Referring toFIG. 4 , the base station device 100 includes an antenna unit 110, awireless communication unit 120, a network communication unit 130, astorage unit 140, and a control unit 150.

(1) Antenna Unit 110

The antenna unit 110 radiates a signal output by the wirelesscommunication unit 120 into space as a radio wave. Further, the antennaunit 110 converts the radio wave in space into a signal, and outputs thesignal to the wireless communication unit 120.

(2) Wireless Communication Unit 120

The wireless communication unit 120 transmits and receives signals. Forexample, the wireless communication unit 120 transmits a downlink signalto the terminal device and receives an uplink signal from the terminaldevice.

(3) Network Communication Unit 130

The network communication unit 130 transmits and receives information.For example, the network communication unit 130 transmits information toanother node and receives information from another node. For example,the another node includes another base station and another core networknode.

(4) Storage Unit 140

The storage unit 140 temporarily or permanently stores a program andvarious data for the operation of the base station device 100.

(5) Control Unit 150

The control unit 150 controls the overall operation of the base stationdevice 100 to provide various functions of the base station device 100.The control unit 150 includes an access right sharing unit 151 and acommunication processing unit 153.

The access right sharing unit 151 has a function of performing a processrelating to sharing of the access right acquired by the terminal device200. For example, the access right sharing unit 151 acquires informationon the radio resource of which the access right is acquired by theterminal device 200. In addition, the access right sharing unit 151performs such a process that the radio resource of which the accessright is acquired by the terminal device 200 is used by the terminaldevice 200 other than the terminal device 200 which acquire the accessright.

The communication processing unit 153 has a function of performingcommunication processing with the terminal device 200. The communicationprocessing unit 153 performs different processes depending on whetherthe radio resource used for communication is the radio resource of whichthe access right is acquired. Specifically, in a case where the radioresource of which the access right is not acquired is used, thecommunication processing unit 153 performs communication by performingchannel access using random back-off. On the other hand, in a case wherethe radio resource of which the access right is acquired by the terminaldevice 200 is used, the communication processing unit 153 performscommunication by performing channel access without using randomback-off.

The control unit 150 may further include other components other thanthese components. That is, the control unit 150 can perform operationsother than the operations of these components.

<2.2. Configuration Example of Terminal Device>

FIG. 5 is a block diagram illustrating an example of a configuration ofthe terminal device 200 according to this embodiment. Referring to FIG.5 , the terminal device 200 includes an antenna unit 210, a wirelesscommunication unit 220, a storage unit 230, and a control unit 240.

(1) Antenna Unit 210

The antenna unit 210 radiates a signal output by the wirelesscommunication unit 220 into space as a radio wave. Further, the antennaunit 210 converts the radio wave in space into a signal, and outputs thesignal to the wireless communication unit 220.

(2) Wireless Communication Unit 220

The wireless communication unit 220 transmits and receives signals. Forexample, the wireless communication unit 220 receives a downlink signalfrom the base station and transmits an uplink signal to the basestation. Further, the wireless communication unit 220 receives asidelink signal from another terminal device 200 and transmits asidelink signal to another terminal device 200.

(3) Storage Unit 230

The storage unit 230 temporarily or permanently stores a program foroperating the terminal device 200 and various data.

(4) Control Unit 240

The control unit 240 controls the overall operation of the terminaldevice 200 to provide various functions of the terminal device 200. Thecontrol unit 240 includes an access right sharing unit 241 and acommunication processing unit 243.

The access right sharing unit 241 performs a process relating to sharingof the access right. The terminal device 200 may acquire the accessright by itself. In that case, the access right sharing unit 241transmits information on the radio resource that acquires the accessright to another communication device (for example, the base stationdevice 100 or another terminal device 200). The terminal device 200 mayshare the access right acquired by another terminal device 200. In thatcase, the access right sharing unit 241 acquires information on theradio resource of which the access right is acquired by the anotherterminal device 200.

The communication processing unit 243 has a function of performingcommunication processing with another communication device. Thecommunication processing unit 243 performs different processes dependingon whether the radio resource used for communication is the radioresource of which the access right is acquired. Specifically, in a casewhere the radio resource of which the access right is not acquired isused, the communication processing unit 243 acquires the access right byperforming channel access using random back-off and then performscommunication. On the other hand, in a case where the radio resource ofwhich the access right is acquired by the terminal device 200 itself oranother terminal device 200 is used, the communication processing unit243 performs communication by performing channel access without usingrandom back-off.

The control unit 240 may further include other components other thanthese components. That is, the control unit 240 can perform operationsother than the operations of these components.

3. Technical Features <3.1. Sharing of Sharable Resource Information>

The terminal device 200 (for example, the communication processing unit243) acquires an access right by performing carrier sense. Specifically,the terminal device 200 performs carrier sense using random back-off,and obtains the access right to the radio resource. Then, the terminaldevice 200 (for example, the access right sharing unit 241) transmitsresource information, which indicates the radio resource available toanother communication device among the radio resources of which theaccess rights are acquired, on the uplink or the sidelink. Accordingly,the another communication device can share the access right acquired bythe terminal device 200. Hereinafter, the another communication deviceis also referred to as a shared communication device. The sharedcommunication device includes the base station device 100 and anotherterminal device 200.

The terminal device 200 that acquires the access right is also referredto as a first terminal device 200. Further, another terminal device 200which is the terminal device 200 and shares the access right acquired bythe first terminal device 200 is also referred to as a second terminaldevice 200. The terminal device 200 can function as both the firstterminal device 200 and the second terminal device 200. In a case wherethe terminal device 200 functions as the first terminal device 200, theresource information transmitted by the first terminal device 200corresponds to first resource information. In a case where the terminaldevice 200 functions as the second terminal device 200, the resourceinformation transmitted from the first terminal device 200 and receivedby the second terminal device 200 corresponds to second resourceinformation.

Among the radio resources of which the access rights are acquired by thefirst terminal device 200, the radio resource available to the sharedcommunication device is also referred to as a sharable resource below.The sharable resource may be regarded as a radio resource of which theaccess right is acquired by the first terminal device 200 or may beregarded as a radio resource not used by the first terminal device 200among the radio resources of which the access rights are acquired by thefirst terminal device 200. Focusing on the time resource, the sharableresource may be regarded as a COT, or may be regarded as a section ofthe COT that is not used by the first terminal device 200. In addition,resource information indicating a sharable resource is hereinafter alsoreferred to as sharable resource information.

<3.2. Sharing of Access Right>

In a case where receiving the sharable resource information, the sharedcommunication device transmits a signal on the basis of the receivedsharable resource information by using the sharable resource. Here, thesharable resource information is information indicating a resourceavailable to another communication device other than the first terminaldevice 200 among radio resources of which the access rights are acquiredby the first terminal device 200 by performing carrier sense.

(1) Sharing by Base Station Device 100

A case where the shared communication device is the base station device100 will be described.

The base station device 100 (for example, communication processing unit153) may use the sharable resource for communication on the basis of thesharable resource information. In that case, the base station device 100transmits a signal using the sharable resource. That is, the basestation device 100 transmits the signal using the radio resource notused by the first terminal device 200 among the radio resources of whichthe access rights are acquired by the first terminal device 200 acquiresthe access right. At that time, the base station device 100 performschannel access without performing carrier sense using random back-off.For example, the base station device 100 may perform carrier sensewithout using random back-off and perform channel access. Further, thebase station device 100 may perform channel access without firstperforming carrier sense. Incidentally, the signal transmissiondestination may be the first terminal device 200 or another terminaldevice 200 connected to the base station device 100.

In addition, the base station device 100 may cause the second terminaldevice 200 to use the sharable resource. In that case, on the basis ofthe sharable resource information, the base station device 100 (forexample, the access right sharing unit 151) transmits a grant message(for example, uplink grant) giving an instruction on the transmission ofa signal in the sharable resource to the terminal device 200(corresponding to the second terminal device 200) other than the firstterminal device 200. Then, the second terminal device 200 transmits asignal (for example, an uplink signal) on the basis of the receivedgrant message by using the sharable resource. More specifically, thesecond terminal device 200 transmits the signal by using the radioresource not used by the first terminal device 200 and the base stationdevice 100 among the radio resources of which the access rights areacquired by the first terminal device 200. At this time, the secondterminal device 200 performs channel access without performing carriersense using random back-off. For example, the second terminal device 200may perform carrier sense without using random back-off and performchannel access. Further, the second terminal device 200 may performchannel access without first performing carrier sense.

In any case, the base station device 100 and the second terminal device200 do not perform carrier sense using random back-off, and thus thewaiting time for channel access is reduced. That is, it is possible toimprove the use efficiency of the radio resources.

(2) Sharing by Second Terminal Device 200

A case where the shared communication device is the second terminaldevice 200 will be described.

The second terminal device 200 (for example, the communicationprocessing unit 243) transmits a signal on the basis of the sharableresource information by using the sharable resource. That is, the secondterminal device 200 transmits the signal using the radio resource notused by the first terminal device 200 among the radio resources of whichthe access rights are acquired by the first terminal device 200. At thistime, the second terminal device 200 performs channel access withoutperforming carrier sense using random back-off. For example, the secondterminal device 200 may perform carrier sense without using randomback-off and perform channel access. Further, the second terminal device200 may perform channel access without first performing carrier sense.

In any case, the second terminal device 200 does not perform carriersense using random back-off, and thus the waiting time for channelaccess is reduced. That is, it is possible to improve the use efficiencyof the radio resources.

(3) Restriction During Sharing

A predetermined restriction may be imposed on the shared communicationdevice at the time of sharing the access right. Specifically, the typeof the signal that can be transmitted using sharable resource may belimited.

For example, the signal that the shared communication device cantransmit by using the sharable resource is limited to a signal includingdata which has a higher channel access priority class than the datatransmitted by the first terminal device 200 (that is, higher priority).Further, the signal that the shared communication device can transmit byusing the sharable resource may be limited to a control signal/controlchannel. Further, the signal that the shared communication device cantransmit by using the sharable resource may be limited to a signalincluding a communication parameter to be used in the sharable resourcedescribed later.

<3.3. Contents of Sharable Resource Information>

The sharable resource information may include various information. Thesharable resource information includes information indicating the radioresource of which the access right is acquired. Further, the sharableresource information may include information indicating a radio resourceto be used.

(1) Information indicating radio resource of which access right isacquired For example, the sharable resource information may includeinformation indicating a radio resource of which the access right isacquired by the first terminal device 200. In this case, the sharableresource information includes information indicating the frequency ofthe radio resource of which the access right is acquired by the firstterminal device 200 and information indicating the time. Accordingly,the shared communication device can recognize the radio resource ofwhich the access right is acquired by the first terminal device 200.

Attention is given to the time information in the information indicatingthe radio resource of which the access right is acquired by the firstterminal device 200. The information indicating the time of the radioresource of which the access right is acquired by the first terminaldevice 200 is information indicating the time during which the channelmay be occupied (that is, COT). The information indicating the COTincludes information indicating the start timing, the end timing, and/orthe length of the COT. Hereinafter, an example will be described.

For example, the sharable resource information may include informationindicating an interval from a time resource at which the sharableresource information is transmitted to a last time resource of the radioresources in which the first terminal device 200 acquires the accessright. In other words, the sharable resource information includesinformation indicating the remaining time of the COT based on the timeresource at which the sharable resource information is transmitted.Here, the time resource is, for example, a symbol, a slot, and/or a subframe, and the information indicating the interval is, for example, thenumber of symbols, the number of slots, and/or the number of sub frames.The shared communication device adds the symbol number, the number ofslots, and/or the sub frame number to the symbol number, the slotnumber, and/or the sub frame number that receives the resourceinformation, so as to recognize for the last symbol, the slot, and/orthe sub frame of the radio resource of which the access right isacquired by the first terminal device 200.

For example, the sharable resource information may include informationindicating the last time resource of the radio resource of which theaccess right is acquired by the first terminal device 200. Here, thetime resource is, for example, a symbol, a slot, and/or a sub frame, andthe information indicating the time resource is, for example, a symbolnumber, a slot number, and/or a sub frame number.

For example, the sharable resource information may include informationindicating the first time resource of the radio resource of which theaccess right is acquired by the first terminal device 200. Here, thetime resource is, for example, a symbol, a slot, and/or a sub frame, andthe information indicating the time resource is, for example, a symbolnumber, a slot number, and/or a sub frame number.

For example, the sharable resource information may include informationindicating a time length (that is, the length of the COT) of the radioresource of which the access right is acquired by the first terminaldevice 200. However, if this information is already known to the sharedcommunication device, the information need not be transmitted in thesharable resource information. For example, in a case where the lengthof the COT is determined by the channel access priority class, thesharable resource information may include information indicating thechannel access priority class.

The example of the information indicating the COT has been describedabove.

(2) Information Indicating Radio Resources to be Used

For example, the sharable resource information may include informationindicating the radio resource to be used by the first terminal device200 (hereinafter, also referred to as a radio resource to be used) amongthe radio resources of which the access rights are acquired by the firstterminal device 200. In this case, the sharable resource informationincludes information indicating the frequency of the radio resource tobe used by the first terminal device 200 among the radio resources ofwhich the access rights are acquired by the first terminal device 200and information indicating the time. With reference to this information,the shared communication device can recognize a radio resource not to beused by the first terminal device 200. Therefore, the sharedcommunication device can efficiently access the sharable resources, forexample, by accessing the radio resource not to be used by the firstterminal device 200.

Attention is given to time information in the information indicating theradio resources to be used. The information indicating the time of theradio resource to be used includes information indicating the starttiming, the end timing, and/or the length of the time resource to beused (that is, the time resource to be used by the first terminal device200 in the COT).

Note that the shared communication device can use the sharable resourceeven if information indicating the radio resource to be used is notprovided. In a case where the information indicating the radio resourceto be used is not provided, on the basis of the information indicatingthe COT, the shared communication device performs carrier sense withoutusing random back-off within the COT regardless of whether the firstterminal device 200 uses or does not use the radio resource. Then, whenthe use of the channel by the first terminal device 200 ends, the sharedcommunication device detects an empty channel and starts using thesharable resource.

The radio resource to be used may be specified by the base stationdevice 100 using RRC signaling or the like. In that case, the basestation device 100 can grasp the radio resources to be used in advancewithout providing information indicating the radio resources to be used.

<3.4. Transmission Method of Sharable Resource Information>

(1) Time resource for transmitting sharable resource information

The first terminal device 200 (for example, the access right sharingunit 241) may transmit the sharable resource information in a part ofthe time resources used continuously.

For example, the first terminal device 200 may transmit the sharableresource information in the first time resource of the time resourcesused continuously. In this case, it is desirable that the sharableresource information includes at least information indicating the endtiming of the COT and information indicating the end timing of the radioresource to be used. Accordingly, the shared communication device canrecognize the radio resources from the end timing of the radio resourceto be used to the end timing of the COT as the sharable resource.

For example, the first terminal device 200 may transmit the sharableresource information in the later time resource of the time resourcesused continuously. In this case, it is desirable that the sharableresource information includes at least information indicating the endtiming of the COT. Accordingly, the shared communication device canshare the access right acquired by the first terminal device 200 untilthe end timing of the COT.

In any case, the shared communication device can recognize the sharableresources with the minimum overhead.

The first terminal device 200 (for example, the access right sharingunit 241) may transmit the sharable resource information in all of thetime resources used continuously. In this case, even if the reception ofthe sharable resource information fails in some time resources, theshared communication device receives the sharable resource informationin another time resource and can share the access right acquired by thefirst terminal device 200.

Hereinafter, the use of the sharable resource by the sharedcommunication device when the sharable resource information istransmitted in all the time resources of the time resources usedcontinuously will be described with reference to FIGS. 6 and 7 .

FIG. 6 is a diagram for describing an example of sharing an access rightaccording to this embodiment. In the example illustrated in FIG. 6 , thebase station device 100 corresponds to a shared communication device.The upper part of FIG. 6 illustrates carrier sense performed by the basestation device 100 and a signal transmitted by the base station device100. The lower part of FIG. 6 illustrates carrier sense performed by thefirst terminal device 200 and a signal transmitted by the first terminaldevice 200. The rectangle described as DL is a time resource fortransmitting a downlink signal. The rectangle described as UL is a timeresource for transmitting a downlink signal.

As illustrated in FIG. 6 , the first terminal device 200 first performscarrier sense using random back-off, and acquires an access right. Next,the first terminal device 200 transmits an uplink signal within the COTon the basis of the acquired access right. At this time, the firstterminal device 200 performs uplink transmission of the sharableresource information in all time resources of the time resources usedcontinuously. In the example illustrated in FIG. 6 , as the sharableresource information, the information indicating the remaining time ofthe COT based on the time resource at which the sharable resourceinformation is transmitted is transmitted. In the example illustrated inFIG. 6 , the first terminal device 200 acquires access rights for eighttime resources. Then, the first terminal device 200 performs uplinktransmission of the sharable resource information indicating that accessrights to the seven remaining time resources are acquired in the firsttime resource.

After that, the first terminal device 200 performs uplink transmissionof the sharable resource information indicating that six, five, and fouraccess rights are acquired for the second, third, and fourth timeresources. The base station device 100 can recognize the remaining timeof the COT on the basis of the sharable resource information. The firstterminal device 200 transmits the fourth uplink signal lastly and stopstransmitting the uplink signal. The base station device 100 recognizesan empty channel by carrier sense without using random back-off in thefifth time resource. That is, the base station device 100 recognizesthat the radio resources from the fifth time resource to the end timingof the COT can be used. Accordingly, as illustrated in FIG. 6 , the basestation device 100 can transmit the downlink signal by using thesharable resource.

The base station device 100 may perform channel access without firstperforming carrier sense. An example in that case is illustrated in FIG.7 . FIG. 7 is a diagram for describing an example of sharing the accessright according to this embodiment. The example illustrated in FIG. 7 isthe same as the example illustrated in FIG. 6 , except that base stationdevice 100 does not perform carrier sense.

(2) Physical Channel on which Sharable Resource Information isTransmitted

The first terminal device 200 (for example, the access right sharingunit 241) can transmit sharable resource information by using variousphysical channels.

Same physical channel as physical channel used for data transmission

The first terminal device 200 may transmit sharable resource informationby using the physical channel used for data transmission. Such physicalchannels include, for example, a Physical uplink shared channel (PUSCH)and a physical sidelink shared channel (PSSCH). In this case, the firstterminal device 200 can collectively apply signal processing such asencoding to data and sharable resource information. Therefore, aresource efficiency can be improved.

Physical channel different from physical channel used for datatransmission The first terminal device 200 may transmit the sharableresource information by using a physical channel different from thephysical channel used for data transmission. Specifically, the firstterminal device 200 multiplexes a physical channel used for datatransmission and a physical channel used for transmission of thesharable resource information by means such as time divisionmultiplexing (TDM) or frequency division multiplexing (FDM) andtransmits the physical channels. Therefore, the first terminal device200 can make the target error rate and the delay requirement differentby applying different MCS or coding methods for the data and thesharable resource information. Further, in a case where the sharableresource information is continuously transmitted in continuous timeresources, the information of the physical channel used for transmissionof the sharable resource information is the same between continuous timeresources. That is, it can be handled as repeated transmission.Therefore, in a case where the sharable resource information isdifferent between continuous time resources, soft-combining of physicalchannels is facilitated, and reception quality can be improved.

Examples of the physical channel different from the physical channelused for data transmission include a physical channel used fortransmission of the control information. Examples of such a physicalchannel include a physical uplink control channel (PUCCH) and a physicalsidelink control channel (PSCCH).

Physical channels that can be received in common between differentoperators

The first terminal device 200 may transmit the sharable resourceinformation by using the physical channel (or the physical signal) thatcan be commonly received by different operators. The first terminaldevice 200 broadcasts the sharable resource information by using such aphysical channel. Then, the base station device and the terminal deviceof an operator different from the operator that provides the firstterminal device 200 with the wireless service can receive the sharableresource information. That is, the base station device and the terminaldevice of the different operator can recognize the radio resources inwhich the access right is acquired by the first terminal device 200.Therefore, the opportunity and accuracy of carrier sense by the basestation device and terminal device of the different operator areimproved. Further, coordination between different operators isfacilitated.

<3.5. Sharing by Second Terminal Device>

Hereinafter, sharing of the access right by the second terminal device200 will be described in detail.

(1) Types of Sharing Access Right

Sharing Access Right Via Base Station Device 100

The sharing of the access right may be performed via the base stationdevice 100. In that case, the first terminal device 200 transmits thesharable resource information to the base station device 100 on theuplink. Then, as described in section 3.2 (1), the second terminaldevice 200 transmits a signal on the basis of the instruction from basestation device 100 by using the sharable resources. This point will bedescribed with reference to FIG. 8 .

FIG. 8 is a diagram for describing an example of sharing the accessright according to this embodiment. In the example illustrated in FIG. 8, the base station device 100 and the second terminal device 200correspond to a shared communication device. The upper part of FIG. 8illustrates carrier sense performed by the base station device 100 and asignal transmitted by the base station device 100. The middle part ofFIG. 8 illustrates carrier sense performed by the first terminal device200 and a signal transmitted by the first terminal device 200. The lowerpart of FIG. 8 illustrates carrier sense performed by the secondterminal device 200 and a signal transmitted by the second terminaldevice 200. The rectangle described as DL is a time resource fortransmitting a downlink signal. The rectangle described as UL is a timeresource for transmitting a downlink signal.

As illustrated in FIG. 8 , the first terminal device 200 first performscarrier sense using random back-off, and acquires an access right. Next,the first terminal device 200 transmits an uplink signal within the COTon the basis of the acquired access right. At this time, the firstterminal device 200 performs uplink transmission of the sharableresource information in all time resources of the time resources usedcontinuously. In the example illustrated in FIG. 8 , as the sharableresource information, the information indicating the remaining time ofthe COT based on the time resource at which the sharable resourceinformation is transmitted is transmitted. In the example illustrated inFIG. 8 , the first terminal device 200 acquires access rights for eighttime resources. Then, the first terminal device 200 performs uplinktransmission of the sharable resource information indicating that accessrights to the seven remaining time resources are acquired in the firsttime resource.

Thereafter, the first terminal device 200 performs uplink transmissionof the sharable resource information indicating that access rights tothe six remaining time resources are acquired in the second timeresource. The base station device 100 can recognize the remaining timeof the COT on the basis of the sharable resource information. The firstterminal device 200 transmits the second uplink signal lastly and stopstransmitting the uplink signal. The base station device 100 recognizesan empty channel by carrier sense without using random back-off in thethird time resource. That is, the base station device 100 recognizesthat the radio resources from the third time resource to the end timingof the COT can be used.

The base station device 100 transmits a downlink signal by using thethird to sixth time resources among the sharable resources. Further, byusing the uplink grant, the base station device 100 instructs the secondterminal device 200 to perform uplink transmission in the seventh andeighth time resources among the sharable resources. Then, the secondterminal device 200 performs carrier sense without using randomback-off, and then transmits an uplink signal by using the seventh andeighth time resources of the sharable resources.

Direct Sharing of Access Rights

The access rights may be shared directly. In that case, the firstterminal device 200 transmits the sharable resource information to thesecond terminal device 200. Typically, the first terminal device 200 maytransmit the sharable resource information to the second terminal device200 on the sidelink. The transmission method to the second terminaldevice 200 is not limited to the sidelink. For example, the firstterminal device 200 may transmit a reference signal for measuringinterference between terminal devices while including sharable resourceinformation. Thereafter, as described in section 3.2 (2), the secondterminal device 200 transmits a signal on the basis of the receivedsharable resource information by using the sharable resources. In thiscase, the second terminal device 200 performs grant-free transmission.This point will be described with reference to FIG. 9 .

FIG. 9 is a diagram for describing an example of sharing the accessright according to this embodiment. In the example illustrated in FIG. 9, the second terminal device 200 corresponds to a shared communicationdevice. The upper part of FIG. 9 illustrates carrier sense performed bythe base station device 100 and a signal transmitted by the base stationdevice 100. The middle part of FIG. 9 illustrates carrier senseperformed by the first terminal device 200 and a signal transmitted bythe first terminal device 200. The lower part of FIG. 9 illustratescarrier sense performed by the second terminal device 200 and a signaltransmitted by the second terminal device 200. The rectangle describedas UL is a time resource for transmitting a downlink signal. Therectangle described as SL is a time resource for transmitting a sidelinksignal.

As illustrated in FIG. 9 , the first terminal device 200 first performscarrier sense using random back-off, and acquires an access right. Next,the first terminal device 200 transmits an uplink signal and a sidelinksignal within the COT on the basis of the acquired access right. At thistime, the first terminal device 200 performs uplink transmission andsidelink transmission of the sharable resource information in all timeresources of the time resources used continuously. In the exampleillustrated in FIG. 9 , as the sharable resource information, theinformation indicating the remaining time of the COT based on the timeresource at which the sharable resource information is transmitted istransmitted. In the example illustrated in FIG. 9 , the first terminaldevice 200 acquires access rights for eight time resources. Then, thefirst terminal device 200 performs uplink transmission and sidelinktransmission of the sharable resource information indicating that accessrights to the seven remaining time resources are acquired in the firsttime resource.

Thereafter, the first terminal device 200 performs uplink transmissionand sidelink transmission of the sharable resource informationindicating that access rights to the six remaining time resources areacquired in the second time resource. The second terminal device 200 canrecognize the remaining time of the COT on the basis of the sharableresource information transmitted by the sidelink. The first terminaldevice 200 transmits the second uplink signal and the sidelink signallastly and stops transmitting the uplink signal and the sidelink signal.The second terminal device 200 recognizes an empty channel by carriersense without using random back-off in the third time resource. That is,the second terminal device 200 recognizes that the radio resources fromthe third time resource to the end timing of the COT can be used.Accordingly, as illustrated in FIG. 9 , the second terminal device 200can transmit the uplink signal by using the sharable resource. At thistime, similarly to the first terminal device 200, the second terminaldevice 200 transmits the sharable resource information on the uplink.Accordingly, for example, after the second terminal device 200 ends theuplink transmission, the base station device 100 can transmit thedownlink signal by using the sharable resource.

(2) Sharable Range of Access Rights Sharable

In a case where the degree of similarity of the communicationenvironment with the first terminal device 200 exceeds a predeterminedvalue, the second terminal device 200 (for example, the communicationprocessing unit 243) transmits a signal on the basis of the sharableresource information by using the sharable resource. This is because itis considered that the higher the degree of similarity of thecommunication environment between the first terminal device 200 and thesecond, the more similar the carrier sense results. In other words, thehigher the degree of similarity in the communication environment betweenthe first terminal device 200 and the second terminal device 200, thehigher the possibility that the signal transmitted on the basis of theaccess right has the same effect on the surroundings. By operating theterminal device 200 that satisfies this condition as the second terminaldevice 200, it is possible to prevent that unexpected interference is begiven to surroundings when the second terminal device 200 transmits asignal by using the sharable resource.

The degree of similarity in the communication environment may bedetermined on the basis of the information indicating the distancebetween the terminal devices 200. For example, whether or not the degreeof similarity of the communication environment exceeds a predeterminedvalue can be determined on the basis of whether or not the path lossbetween the terminal devices 200 or the geographic distance between theterminal devices 200 is equal to or less than a predetermined value.This point will be described specifically with reference to FIG. 10 .

FIG. 10 is a diagram for describing sharing of the access right by thesecond terminal device 200 according to this embodiment. As illustratedin FIG. 10 , terminal devices 200A, 200B, and 200C are located in cell11 operated by the base station device 100, and each device iscommunicating with the base station device 100. There is a largepossibility that the influence on the surroundings is similarly givenbetween the terminal devices 200 with close transmission points.Therefore, it is desirable that a plurality of terminal devices 200 withclose transmission points shares the access right. In the exampleillustrated in FIG. 10 , it is assumed that the terminal device 200Afunctions as the first terminal device 200 and acquires the accessright. The terminal device 200A can detect the signal transmitted fromthe communication device located within a carrier sense range 12 bycarrier sense. Incidentally, the carrier sense range 12 is a rangecapable of giving an influence (that is, interference) when the terminaldevice 200A transmits a signal, and is expanded/contracted according totransmission power assumed to be used when the terminal device 200Atransmits a signal. The terminal device 200B is located within thecarrier sense range 12, and thus the influence on the surroundings islikely to be the same as that of the terminal device 200A. Therefore, itis desirable that the terminal device 200B functions as the secondterminal device 200 and shares the access right acquired by the terminaldevice 200A. On the other hand, the terminal device 200C is locatedoutside the carrier sense range 12, and thus the influence on thesurroundings is likely to be different from that of the terminal device200A. Therefore, it is desirable that the terminal device 200C does notshare the access right acquired by the terminal device 200A.

The degree of similarity in the communication environment may bedetermined on the basis of the information on the interferencesituation. For example, whether or not the degree of similarity in thecommunication environment exceeds a predetermined value can bedetermined on the basis of whether or not a difference in a receivedsignal strength indicator (RSSI) or the degree of channel congestionbetween the terminal devices 200 is equal to or smaller than apredetermined value.

The degree of similarity in the communication environment may bedetermined on the basis of the information about the transmissiondestination. For example, whether or not the degree of similarity in thecommunication environment exceeds a predetermined value can bedetermined on the basis of whether or not a difference in the directionof the transmission destination or the direction of the beam between theterminal devices 200 is equal to or smaller than a predetermined value.Incidentally, this index is particularly useful when carrier sense usinga beam form is performed.

The plurality of terminal devices 200 that can share the access rightmay be grouped. The grouping is performed on the basis of, for example,the degree of similarity in the communication environment describedabove. The grouping is typically performed by the base station device100 (for example, the access right sharing unit 151). Then, eachterminal device 200 is set from the base station device 100 with theinformation indicating the group to which the terminal device belongs.

(3) Sharable Resource Information

In the following, regarding the sharing of the access right by thesecond terminal device 200, the information that may be included in thesharable resource information will be described.

Information on Communication Environment

The sharable resource information may include the information on thecommunication environment described above. Accordingly, the secondterminal device 200 can calculate the degree of similarity in thecommunication environment with the first terminal device 200 on thebasis of the received sharable resource information and determinewhether or not the access right can be shared.

For example, the sharable resource information may include theinformation indicating the geographical position or transmission powerof the first terminal device 200. Accordingly, the second terminaldevice 200 can determine the degree of similarity in the communicationenvironment on the basis of the information indicating the distancebetween the terminal devices 200.

For example, the sharable resource information may include informationindicating the RSSI of the first terminal device 200 or the degree ofchannel congestion. Accordingly, the second terminal device 200 candetermine the degree of similarity in the communication environment onthe basis of the information on the interference situation.

For example, the sharable resource information may include theinformation indicating the transmission-destination direction or thebeam direction of the first terminal device 200. Accordingly, the secondterminal device 200 can determine the degree of similarity in thecommunication environment on the basis of the information regarding thetransmission destination.

Group Information

The sharable resource information may include the information indicatingthe group that can share the access right. The information indicatingthe group that can share the access right may include the identificationinformation such as the ID and C-RNTI of each of the plurality ofterminal devices 200 that can share the access right, the ID of thegroup, and the like. With reference to the information which is includedin the received sharable resource information and indicates the groupthat can share the access right, the second terminal device 200 candetermine whether or not the access right can be shared on the basis ofthe received sharable resource information.

For example, the first terminal device 200 transmits the informationindicating the group to which the first terminal device 200 belongswhile being included in the sharable resource information. If the groupto which the first terminal device 200 belongs is the same as that ofthe second terminal device 200, the second terminal device 200determines that the access right acquired by the first terminal device200 can be shared.

(4) Communication Parameter

The first terminal device 200 and the second terminal device 200 sharecommunication parameters to be used in the sharable resources.

The first terminal device 200 and the second terminal device 200 maydirectly share the communication parameters to be used in the sharableresources by D2D communication. Alternatively, the first terminal device200 and the second terminal device 200 may indirectly share thecommunication parameters to be used in the sharable resources via thebase station device 100. In addition, the base station device 100 maydetermine the communication parameters to be used in the sharableresources and transmit the communication parameters to each terminaldevice 200.

An example of information that can be included in the communicationparameters will be described below.

Upper Limit of Transmission Power

The communication parameter to be used in the sharable resource mayinclude the information indicating the upper limit of the transmissionpower that can be used by the second terminal device 200 in the sharableresource.

The second terminal device 200 (for example, the communicationprocessing unit 243) transmits a signal with transmission power equal toor less than the transmission power assumed in the carrier senseperformed when the first terminal device 200 acquires the access right.For example, in the example illustrated in FIG. 10 , the terminal device200B transmits a signal in the sharable resource by using transmissionpower equal to or less than transmission power assumed in carrier senseperformed when the terminal device 200A acquires the access right.Accordingly, it is possible to prevent unexpected interference fromoccurring when the second terminal device 200 transmits a signal in thesharable resource.

Parameters for Channel Access

The communication parameters to be used in the sharable resource mayinclude parameters for channel access.

It is desirable that the first terminal device 200 and the secondterminal device 200 use the parameters of the same channel access. Whenat least a part of the parameters for channel access is updated, it isdesirable that the updated parameters for channel access be shared.

The parameters for channel access include the size of the contentionwindow and the threshold for carrier sense. Further, the parameters forchannel access include a maximum transmission power, an antenna gain,and a beam gain.

(5) Supplement

The second terminal device 200 may be plural. In that case, theplurality of second terminal devices 200 uses the sharable resources inorder, for example. In a case where the plurality of second terminaldevices 200 supports non-orthogonal multiple access (NOMA)communication, signal may be non-orthogonal (NOMA) multiplexed in thesame sharable resource to be transmitted.

In a case where the first terminal device 200 and the second terminaldevice 200 support NOMA communication, signals may be non-orthogonalmultiplexed in the same radio resource to be transmitted. In this case,the second terminal device 200 can transmit the signal without waitingfor the first terminal device 200 to end using the radio resource.

<3.6. Processing Flow>

(1) Process Flow by First Terminal Device 200

FIG. 11 is a flowchart illustrating an example of a flow of an accessright sharing process executed by the first terminal device 200according to this embodiment.

As illustrated in FIG. 11 , first, the communication processing unit 243performs carrier sense using random back-off, and acquires an accessright (Step S102). Next, the access right sharing unit 241 performsuplink transmission and/or sidelink transmission of the signal of thetransmission target and the sharable resource information in the radioresource of which the access right is acquired (Step S104).

(2) Flow of Process by Base Station Device 100

FIG. 12 is a flowchart illustrating an example of a flow of an accessright sharing process performed by the base station device 100 accordingto this embodiment.

As illustrated in FIG. 12 , first, the access right sharing unit 151receives the sharable resource information transmitted from the firstterminal device 200 by the uplink (Step S202). Next, the communicationprocessing unit 153 performs carrier sense without using random back-offon the sharable resource, and recognizes the end of transmission of thefirst terminal device 200 (Step S204). Next, the communicationprocessing unit 153 transmits a downlink signal in the sharable resource(Step S206). Next, the access right sharing unit 151 transmits an uplinkgrant instructing to perform uplink transmission in the sharableresource to the second terminal device 200 (Step S208). Then, thecommunication processing unit 153 receives the uplink signal from thesecond terminal device 200 in the sharable resource (Step S210).

Incidentally, Steps S206 and S208 described above may be performedsimultaneously, or the order may be reversed.

(3) Flow of Process by Second Terminal Device 200

FIG. 13 is a flowchart illustrating an example of a flow of the accessright sharing process executed by the second terminal device 200according to this embodiment. This flow illustrates an example in a casewhere the access right is shared via the base station device 100 asdescribed above with reference to FIG. 8 .

As illustrated in FIG. 13 , first, the access right sharing unit 241gives an instruction to perform uplink transmission in the sharableresource of which the access right is acquired by the first terminaldevice 200.

The uplink grant is received from the base station device 100 (StepS302). Then, the communication processing unit 243 transmits an uplinksignal in the sharable resource according to the uplink grant (StepS304).

FIG. 14 is a flowchart illustrating an example of the flow of the accessright sharing process performed by the second terminal device 200according to this embodiment. This flow illustrates an example in a casewhere the access right is directly shared as described above withreference to FIG. 9 .

As illustrated in FIG. 14 , first, the access right sharing unit 241receives the sharable resource information transmitted from the firstterminal device 200 by the sidelink (Step S402). Next, the communicationprocessing unit 243 performs carrier sense without using random back-offin the sharable resource, and recognizes the end of transmission of thefirst terminal device 200 (Step S404). Then, the communicationprocessing unit 243 transmits a sidelink signal or an uplink signal inthe sharable resource (Step S406).

4. Application Examples

The technology according to the present disclosure can be applied tovarious products. For example, the base station device 100 may berealized as any type of evolved Node B (eNB) such as a macro eNB or asmall eNB. The small eNB may be an eNB that covers a cell, such as apico eNB, a micro eNB, or a home (femto) eNB, smaller than a macro cell.Instead, the base station device 100 may be realized as another type ofbase station such as a NodeB or a base transceiver station (BTS). Thebase station device 100 may include a main entity (also referred to as abase station device) that controls wireless communication and one ormore remote radio heads (RRHs) disposed at different locations from themain entity. Further, various types of terminals to be described belowmay operate as the base station device 100 by performing a base stationfunction temporarily or semi-permanently.

For example, the terminal device 200 may be realized as a mobileterminal such as a smartphone, a tablet personal computer (PC), anotebook PC, a portable game terminal, a portable/dongle mobile routeror a digital camera, or an in-vehicle terminal such as a car navigationdevice. Further, the terminal device 200 may be realized as a terminalthat performs machine to machine (M2M) communication (also referred toas a machine type communication (MTC) terminal). Moreover, the terminaldevice 200 may be a wireless communication module (for example, anintegrated circuit module configured on one die) mounted on theseterminals.

<4.1. Application Example of Base Station Device> First ApplicationExample

FIG. 15 is a block diagram illustrating a first example of a schematicconfiguration of an eNB to which the technology according to the presentdisclosure may be applied. An eNB 800 includes one or more antennas 810and a base station device 820. Each antenna 810 and the base stationdevice 820 may be connected to each other via an RF cable.

Each of the antennas 810 includes a single or a plurality of antennaelements (for example, a plurality of antenna elements constituting aMIMO antenna) and is used for the base station device 820 to transmitand receive a wireless signal. The eNB 800 may include a plurality ofthe antennas 810 as illustrated in FIG. 15 , and the plurality ofantennas 810 may correspond to, for example, a plurality of frequencybands used by the eNB 800, respectively. Incidentally, although FIG. 15illustrates an example in which the eNB 800 includes the plurality ofantennas 810, the eNB 800 may include the single antenna 810.

The base station device 820 includes a controller 821, a memory 822, anetwork interface 823, and a wireless communication interface 825.

The controller 821 may be, for example, a CPU or a DSP, and operatesvarious functions of an upper layer of the base station device 820. Forexample, the controller 821 generates a data packet from data in asignal processed by the wireless communication interface 825, andtransfers the generated packet via the network interface 823. Thecontroller 821 may generate a bundled packet by bundling data from aplurality of base band processors to transfer the generated bundledpacket. Further, the controller 821 may also have a logical function ofperforming control such as radio resource control, radio bearer control,mobility management, admission control, and scheduling. Further, thecontrol may be performed in cooperation with a surrounding eNB or a corenetwork node. The memory 822 includes a RAM and a ROM, and stores aprogram executed by the controller 821 and a variety of control data(such as terminal list, transmission power data, and scheduling data).

The network interface 823 is a communication interface for connectingthe base station device 820 to the core network 824. The controller 821may communicate with a core network node or another eNB via the networkinterface 823. In this case, the eNB 800 may be connected to a corenetwork node or another eNB through a logical interface (for example, S1interface or X2 interface). The network interface 823 may be a wiredcommunication interface or a wireless communication interface forwireless backhaul. In the case where the network interface 823 is awireless communication interface, the network interface 823 may use ahigher frequency band for wireless communication than a frequency bandused by the wireless communication interface 825.

The wireless communication interface 825 supports a cellularcommunication system such as long term evolution (LTE) or LTE-Advanced,and provides wireless connection to a terminal located within the cellof the eNB 800 via the antenna 810. The wireless communication interface825 may typically include a base band (BB) processor 826, an RF circuit827, and the like. The BB processor 826 may, for example, performencoding/decoding, modulation/demodulation, multiplexing/demultiplexing,and the like, and performs a variety of signal processing on each layer(for example, L1, medium access control (MAC), radio link control (RLC),and packet data convergence protocol (PDCP)). The BB processor 826 mayhave part or all of the logical functions as described above instead ofthe controller 821. The BB processor 826 may be a module including amemory having a communication control program stored therein, aprocessor to execute the program, and a related circuit, and thefunction of the BB processor 826 may be changeable by updating theprogram. Further, the module may be a card or blade to be inserted intoa slot of the base station device 820, or a chip mounted on the card orthe blade. On the other hand, the RF circuit 827 may include a mixer, afilter, an amplifier, and the like, and transmits and receives awireless signal via the antenna 810.

The wireless communication interface 825 includes a plurality of BBprocessors 826 as illustrated in FIG. 15 , and the plurality of BBprocessors 826 may correspond to a plurality of frequency bands used bythe eNB 800, for example. Further, the wireless communication interface825 may also include a plurality of the RF circuits 827, as illustratedin FIG. 15 , and the plurality of RF circuits 827 may, for example,correspond to a plurality of antenna elements, respectively. Note thatFIG. 15 illustrates an example in which the wireless communicationinterface 825 includes a plurality of BB processors 826 and a pluralityof RF circuits 827, but the wireless communication interface 825 mayinclude a single BB processor 826 or a single RF circuit 827.

In the eNB 800 illustrated in FIG. 15 , one or more components (theaccess right sharing unit 151 and/or the communication processing unit153) included in the control unit 150 described with reference to FIG. 4may be implemented in the wireless communication interface 825.Alternatively, at least some of these components may be implemented inthe controller 821. As an example, the eNB 800 may be implemented with amodule including a part (for example, the BB processor 826) or all ofthe wireless communication interface 825, and/or the controller 821, andthe module may be mounted with one or more of the components. In thiscase, the module may store a program for causing the processor tofunction as the one or more components (in other words, a program forcausing the processor to execute the operations of the one or morecomponents) and execute the program. As another example, a program forcausing the processor to function as the one or more components may beinstalled in the eNB 800, and the wireless communication interface 825(for example, the BB processor 826) and/or the controller 821 mayexecute the program. As described above, the eNB 800, the base stationdevice 820, or the module may be provided as a device including the oneor more components, and a program for causing the processor to functionas the one or more components may be provided. Further, a readablerecording medium on which the above-described program is recorded may beprovided.

In the eNB 800 illustrated in FIG. 15 , the wireless communication unit120 described with reference to FIG. 4 may be implemented in thewireless communication interface 825 (for example, the RF circuit 827).Further, the antenna unit 110 may be implemented in the antenna 810.Further, the network communication unit 130 may be implemented in thecontroller 821 and/or the network interface 823. Further, the storageunit 140 may be implemented in the memory 822.

Second Application Example

FIG. 16 is a block diagram illustrating a second example of a schematicconfiguration of an eNB to which the technology according to the presentdisclosure may be applied. An eNB 830 includes one or more antennas 840,a base station device 850, and an RRH 860. Each of the antennas 840 andthe RRH 860 may be connected to each other via an RF cable. Further, thebase station device 850 and the RRH 860 may be connected to each otherby a high speed line such as optical fiber cables.

Each of the antennas 840 includes a single or a plurality of antennaelements (for example, a plurality of antenna elements constituting aMIMO antenna), and is used for the RRH 860 to transmit and receive awireless signal. The eNB 830 may include a plurality of the antennas 840as illustrated in FIG. 16 , and the plurality of antennas 840 maycorrespond to, for example, a plurality of frequency bands used by theeNB 830, respectively. Incidentally, although FIG. 16 illustrates anexample in which the eNB 830 includes the plurality of antennas 840, theeNB 830 may include the single antenna 840.

The base station device 850 includes a controller 851, a memory 852, anetwork interface 853, a wireless communication interface 855, and aconnection interface 857. The controller 851, the memory 852, and thenetwork interface 853 are similar to the controller 821, the memory 822,and the network interface 823 described with reference to FIG. 15 .

The wireless communication interface 855 supports a cellularcommunication system such as LTE and LTE-Advanced, and provides wirelessconnection to a terminal located in a sector corresponding to the RRH860 via the RRH 860 and the antenna 840. The wireless communicationinterface 855 may typically include a BB processor 856 or the like. TheBB processor 856 is similar to the BB processor 826 described withreference to FIG. 15 except that the BB processor 856 is connected to anRF circuit 864 of the RRH 860 via the connection interface 857. Thewireless communication interface 855 may include a plurality of the BBprocessors 856 as illustrated in FIG. 16 , and the plurality of BBprocessors 856 may correspond to, for example, a plurality of frequencybands used by the eNB 830, respectively. Note that FIG. 16 illustratesan example in which the wireless communication interface 855 includesthe plurality of BB processors 856, but the wireless communicationinterface 855 may include the single BB processor 856.

The connection interface 857 is an interface for connecting the basestation device 850 (wireless communication interface 855) to the RRH860. The connection interface 857 may be a communication module forcommunication on the high speed line which connects the base stationdevice 850 (wireless communication interface 855) to the RRH 860.

The RRH 860 includes a connection interface 861 and a wirelesscommunication interface 863.

The connection interface 861 is an interface for connecting the RRH 860(wireless communication interface 863) to the base station device 850.The connection interface 861 may be a communication module forcommunication on the high speed line.

The wireless communication interface 863 transmits and receives awireless signal via the antenna 840. The wireless communicationinterface 863 may typically include the RF circuit 864 or the like. TheRF circuit 864 may include a mixer, a filter, an amplifier, and thelike, and transmits and receives a wireless signal via the antenna 840.The wireless communication interface 863 may include a plurality of theRF circuits 864 as illustrated in FIG. 16 , and the plurality of RFcircuits 864 may, for example, correspond to a plurality of antennaelements, respectively. Note that FIG. 16 illustrates an example inwhich the wireless communication interface 863 includes the plurality ofRF circuits 864, but the wireless communication interface 863 mayinclude the single RF circuit 864.

In the eNB 830 illustrated in FIG. 16 , one or more components (theaccess right sharing unit 151 and/or the communication processing unit153) included in the control unit 150 described with reference to FIG. 4may be implemented in the wireless communication interface 855 and/orthe wireless communication interface 863. Alternatively, at least someof these components may be implemented in the controller 851. As anexample, the eNB 830 may be mounted with a module including a part (forexample, the BB processor 856) or all of the wireless communicationinterface 855 and/or the controller 851, and the module may beimplemented with one or more of the components. In this case, the modulemay store a program for causing the processor to function as the one ormore components (in other words, a program for causing the processor toexecute the operations of the one or more components) and execute theprogram. As another example, a program for causing the processor tofunction as the one or more components may be installed in the eNB 830,and the wireless communication interface 855 (for example, the BBprocessor 856) and/or the controller 851 may execute the program. Asdescribed above, the eNB 830, the base station device 850, or the modulemay be provided as a device including the one or more components, and aprogram for causing the processor to function as the one or morecomponents may be provided. Further, a readable recording medium onwhich the above-described program is recorded may be provided.

In the eNB 830 illustrated in FIG. 16 , for example, the wirelesscommunication unit 120 described with reference to FIG. 4 may beimplemented in the wireless communication interface 863 (for example,the RF circuit 864). Further, the antenna unit 110 may be implemented inthe antenna 840. Further, the network communication unit 130 may beimplemented in the controller 851 and/or the network interface 853.Further, the storage unit 140 may be implemented in the memory 852.

<4.2. Application Example of Terminal Device> First Application Example

FIG. 17 is a block diagram illustrating an example of a schematicconfiguration of a smartphone 900 to which the technology according tothe present disclosure may be applied. The smartphone 900 includes aprocessor 901, a memory 902, a storage 903, an external connectioninterface 904, a camera 906, a sensor 907, a microphone 908, an inputdevice 909, a display device 910, a speaker 911, a wirelesscommunication interface 912, one or more antenna switches 915, one ormore antennas 916, a bus 917, a battery 918, and an auxiliary controller919.

The processor 901 may be, for example, a CPU or a system on chip (SoC),and controls the functions of an application layer and other layers ofthe smartphone 900. The memory 902 includes a RAM and a ROM, and storesa program executed by the processor 901 and data. The storage 903 mayinclude a storage medium such as semiconductor memories and hard disks.The external connection interface 904 is an interface for connecting anexternally attached device such as memory cards and universal serial bus(USB) devices to the smartphone 900.

The camera 906 includes, for example, an image sensor such as chargecoupled devices (CCDs) and complementary metal oxide semiconductor(CMOS), and generates a captured image. The sensor 907 may include asensor group including, for example, a positioning sensor, a gyrosensor, a geomagnetic sensor, an acceleration sensor, and the like. Themicrophone 908 converts a sound that is input into the smartphone 900 toan audio signal. The input device 909 includes, for example, a touchsensor which detects that a screen of the display device 910 is touched,a key pad, a keyboard, a button, a switch, or the like, and accepts anoperation or an information input from a user. The display device 910includes a screen such as liquid crystal displays (LCDs) and organiclight emitting diode (OLED) displays, and displays an output image ofthe smartphone 900. The speaker 911 converts the audio signal that isoutput from the smartphone 900 to a sound.

The wireless communication interface 912 supports a cellularcommunication system such as LTE or LTE-Advanced, and performs wirelesscommunication. The wireless communication interface 912 may typicallyinclude BB processor 913, RF circuit 914, and the like. The BB processor913 may, for example, perform encoding/decoding,modulation/demodulation, multiplexing/demultiplexing, and the like, andperforms a variety of types of signal processing for wirelesscommunication. On the other hand, the RF circuit 914 may include amixer, a filter, an amplifier, and the like, and transmits and receivesa wireless signal via the antenna 916. The wireless communicationinterface 912 may be a one-chip module in which the BB processor 913 andthe RF circuit 914 are integrated. The wireless communication interface912 may include a plurality of BB processors 913 and a plurality of RFcircuits 914 as illustrated in FIG. 17 . Note that FIG. 17 illustratesan example in which the wireless communication interface 912 includes aplurality of BB processors 913 and a plurality of RF circuits 914, butthe wireless communication interface 912 may include a single BBprocessor 913 or a single RF circuit 914.

The wireless communication interface 912 may support other types ofwireless communication system such as a short range wirelesscommunication system, a near field communication system, and a wirelesslocal area network (LAN) system in addition to the cellularcommunication system, and in this case, the wireless communicationinterface 912 may include the BB processor 913 and the RF circuit 914for each wireless communication system.

Each antenna switch 915 switches a connection destination of the antenna916 among a plurality of circuits (for example, circuits for differentwireless communication systems) included in the wireless communicationinterface 912.

Each of the antennas 916 includes one or more antenna elements (forexample, a plurality of antenna elements constituting a MIMO antenna)and is used for transmission and reception of the wireless signal by thewireless communication interface 912. The smartphone 900 may include aplurality of antennas 916 as illustrated in FIG. 17 . Note that FIG. 17illustrates an example in which the smartphone 900 includes a pluralityof antennas 916, but the smartphone 900 may include a single antenna916.

The smartphone 900 may include the antenna 916 for each wirelesscommunication system. In this case, the antenna switch 915 may beomitted from a configuration of the smartphone 900.

The bus 917 connects the processor 901, the memory 902, the storage 903,the external connection interface 904, the camera 906, the sensor 907,the microphone 908, the input device 909, the display device 910, thespeaker 911, the wireless communication interface 912, and the auxiliarycontroller 919 to each other. The battery 918 supplies electric power toeach block of the smartphone 900 illustrated in FIG. 17 via a feederline that is partially indicated by a broken line in the drawing. Theauxiliary controller 919, for example, operates a minimally necessaryfunction of the smartphone 900 in a sleep mode.

In the smartphone 900 illustrated in FIG. 17 , one or more components(the access right sharing unit 241 and/or the communication processingunit 243) included in the control unit 240 described with reference toFIG. 5 may be implemented in the wireless communication interface 912.Alternatively, at least some of these components may be implemented inthe processor 901 or the auxiliary controller 919. As an example, thesmartphone 900 may be mounted with a module including a part (forexample, the BB processor 913) or all of the wireless communicationinterface 912, the processor 901 and/or the auxiliary controller 919,and the module may be implemented with one or more of the components. Inthis case, the module may store a program for causing the processor tofunction as the one or more components (in other words, a program forcausing the processor to execute the operations of the one or morecomponents) and execute the program. As another example, a program forcausing the processor to function as the one or more components may beinstalled in the smartphone 900, and the wireless communicationinterface 912 (for example, the BB processor 913), the processor 901,and/or the auxiliary controller 919 may execute the program. Asdescribed above, the smartphone 900 or the module may be provided as adevice including the one or more components, and a program for causingthe processor to function as the one or more components may be provided.Further, a readable recording medium on which the above-describedprogram is recorded may be provided.

In the smartphone 900 illustrated in FIG. 17 , for example, the wirelesscommunication unit 220 described with reference to FIG. 5 may beimplemented in the wireless communication interface 912 (for example,the RF circuit 914). Further, the antenna unit 210 may be implemented inthe antenna 916. Further, the storage unit 230 may be implemented in thememory 902.

Second Application Example

FIG. 18 is a block diagram illustrating an example of a schematicconfiguration of a car navigation device 920 to which the technologyaccording to the present disclosure may be applied. The car navigationdevice 920 includes a processor 921, a memory 922, a global positioningsystem (GPS) module 924, a sensor 925, a data interface 926, a contentplayer 927, a storage medium interface 928, an input device 929, adisplay device 930, a speaker 931, a wireless communication interface933, one or more antenna switches 936, one or more antennas 937, and abattery 938.

The processor 921 may be, for example, a CPU or an SoC, and controls thenavigation function and the other functions of the car navigation device920. The memory 922 includes a RAM and a ROM, and stores a programexecuted by the processor 921 and data.

The GPS module 924 uses a GPS signal received from a GPS satellite tomeasure the position (for example, latitude, longitude, and altitude) ofthe car navigation device 920. The sensor 925 may include a sensor groupincluding, for example, a gyro sensor, a geomagnetic sensor, and abarometric sensor. The data interface 926 is, for example, connected toan in-vehicle network 941 via a terminal that is not illustrated, andacquires data such as vehicle speed data generated on the vehicle side.

The content player 927 reproduces content stored in a storage medium(for example, CD or DVD) inserted into the storage medium interface 928.The input device 929 includes, for example, a touch sensor which detectsthat a screen of the display device 930 is touched, a button, a switch,or the like, and accepts operation or information input from a user. Thedisplay device 930 includes a screen such as LCDs and OLED displays, anddisplays an image of the navigation function or the reproduced content.The speaker 931 outputs a sound of the navigation function or thereproduced content.

The wireless communication interface 933 supports a cellularcommunication system such as LTE or LTE-Advanced, and performs wirelesscommunication. The wireless communication interface 933 may typicallyinclude a BB processor 934, an RF circuit 935, and the like. The BBprocessor 934 may, for example, perform encoding/decoding,modulation/demodulation, multiplexing/demultiplexing, and the like, andperforms a variety of types of signal processing for wirelesscommunication. On the other hand, the RF circuit 935 may include amixer, a filter, an amplifier, and the like, and transmits and receivesa wireless signal via the antenna 937. The wireless communicationinterface 933 may be a one-chip module in which the BB processor 934 andthe RF circuit 935 are integrated. The wireless communication interface933 may include a plurality of BB processors 934 and a plurality of RFcircuits 935 as illustrated in FIG. 18 . Note that FIG. 18 illustratesan example in which the wireless communication interface 933 includes aplurality of BB processors 934 and a plurality of RF circuits 935, butthe wireless communication interface 933 may include a single BBprocessor 934 or a single RF circuit 935.

The wireless communication interface 933 may support other types ofwireless communication system such as a short range wirelesscommunication system, a near field communication system, and a wirelessLAN system in addition to the cellular communication system, and in thiscase, the wireless communication interface 933 may include the BBprocessor 934 and the RF circuit 935 for each wireless communicationsystem.

Each antenna switch 936 switches a connection destination of the antenna937 among a plurality of circuits (for example, circuits for differentwireless communication systems) included in the wireless communicationinterface 933.

Each of the antennas 937 includes one or more antenna elements (forexample, a plurality of antenna elements constituting a MIMO antenna)and is used for transmission and reception of the wireless signal by thewireless communication interface 933. The car navigation device 920 mayinclude a plurality of antennas 937 as illustrated in FIG. 18 . Notethat FIG. 18 illustrates an example in which the car navigation device920 includes a plurality of antennas 937, but the car navigation device920 may include a single antenna 937.

The car navigation device 920 may include the antenna 937 for eachwireless communication system. In this case, the antenna switch 936 maybe omitted from a configuration of the car navigation device 920.

The battery 938 supplies electric power to each block of the carnavigation device 920 illustrated in FIG. 18 via a feeder line that ispartially indicated by a broken line in the drawing. Further, thebattery 938 accumulates the electric power supplied from the vehicle.

In the car navigation device 920 illustrated in FIG. 18 , one or morecomponents (the access right sharing unit 241 and/or the communicationprocessing unit 243) included in the control unit 240 described withreference to FIG. 5 may be implemented in the wireless communicationinterface 933. Alternatively, at least some of these components may beimplemented in the processor 921. As an example, the car navigationdevice 920 may be mounted with a module including a part (for example,the BB processor 934) or all of the wireless communication interface 933and/or the processor 921, and the module may be implemented with one ormore of the components. In this case, the module may store a program forcausing the processor to function as the one or more components (inother words, a program for causing the processor to execute theoperations of the one or more components) and execute the program. Asanother example, a program for causing the processor to function as theone or more components may be installed in the car navigation device920, and the wireless communication interface 933 (for example, the BBprocessor 934) and/or the processor 921 may execute the program. Asdescribed above, the car navigation device 920 or the module may beprovided as a device including the one or more components, and a programfor causing the processor to function as the one or more components maybe provided. Further, a readable recording medium on which theabove-described program is recorded may be provided.

In the car navigation device 920 illustrated in FIG. 18 , for example,the wireless communication unit 220 described with reference to FIG. 5may be implemented in the wireless communication interface 933 (forexample, the RF circuit 935). Further, the antenna unit 210 may beimplemented in the antenna 937. Further, the storage unit 230 may beimplemented in the memory 922.

The technology of the present disclosure may also be realized as anin-vehicle system (or a vehicle) 940 including one or more blocks of theabove-described car navigation device 920, the in-vehicle network 941,and a vehicle module 942. The vehicle module 942 generates vehicle datasuch as vehicle speed, engine speed, and trouble information, andoutputs the generated data to the in-vehicle network 941.

5. Conclusion

The embodiment of the present disclosure has been described above indetail with reference to FIGS. 1, 2, 3A, 3B, 3C, 4, 5, 6, 7, 8, 9, 10,11, 12, 13, 14, 15, 16, 17, and 18 . As described above, the firstterminal device 200 according to this embodiment transmits the sharableresource information, which indicates the radio resource available toanother communication device among the radio resources of which theaccess rights are acquired by performing carrier sense using randomback-off, on the uplink or the sidelink. Accordingly, the anothercommunication device can transmit a signal by sharing the access rightacquired by the first terminal device 200. Here, the access right isalready acquired by the first terminal device 200, and thus the anothercommunication device performs channel access without performing carriersense using random back-off. Therefore, compared to a case where thecarrier sense using random back-off is performed, the waiting time forchannel access is reduced, and the use efficiency of radio resources canbe improved.

The preferred embodiments of the present disclosure have been describedabove in detail with reference to the accompanying drawings, but thetechnical scope of the present disclosure is not limited to suchexamples. It is obvious that a person with ordinary knowledge in the artto which the present disclosure pertains can come up with variouschanges or modifications within the scope of the technical ideadescribed in the claims. Of course, it is understood that they belong tothe technical scope of the present disclosure.

Further, the processes described with reference to the flowcharts andthe sequence diagrams in this specification do not necessarily have tobe executed in the illustrated order. Some processing Steps may beperformed in parallel. Further, additional processing Steps may beemployed, and some processing Steps may be omitted.

Further, the effects described in this specification are merelyillustrative or exemplary and are not limited. That is, the technologyaccording to the present disclosure can exhibit other effects that areapparent to those skilled in the art from the description of thisspecification in addition to or instead of the above effects.

Note that the following configurations also belong to the technicalscope of the present disclosure.

(1)

A terminal device comprising:

-   -   a control unit configured to transmit first resource        information, which indicates a radio resource available to        another communication device among radio resources of which        access rights are acquired by performing carrier sense, on an        uplink or a sidelink.

(2)

The terminal device according to claim 1), wherein the first resourceinformation includes information indicating a radio resource of which anaccess right is acquired by the terminal device.

(3)

The terminal device according to claim 2), wherein the first resourceinformation includes information indicating an interval from a timeresource in which the first resource information is transmitted to alast time resource of a radio resource of which an access right isacquired by the terminal device.

(4)

The terminal device according to claim 2) or 3), wherein the firstresource information includes information indicating a last timeresource of a radio resource of which an access right is acquired by theterminal device.

(5)

The terminal device according to any one of claims 2)˜4), wherein thefirst resource information includes information indicating a first timeresource of a radio resource of which an access right is acquired by theterminal device.

(6)

The terminal device according to any one of claims 2)˜5), wherein thefirst resource information includes information indicating a channelaccess priority class of a radio resource of which an access right isacquired by the terminal device.

(7)

The terminal device according to any one of claims 2)˜6), wherein thefirst resource information includes information indicating a radioresource to be used by the terminal device among radio resources ofwhich access rights are acquired by the terminal device.

(8)

The terminal device according to any one of claims 1)˜7), wherein thecontrol unit transmits the first resource information in a part of timeresources used continuously.

(9)

The terminal device according to any one of claims 1)˜7), wherein thecontrol unit transmits the first resource information in all of timeresources used continuously.

(10)

The terminal device according to any one of claims 1)˜9), wherein thecontrol unit transmits the first resource information by using aphysical channel different from a physical channel used for datatransmission.

(11)

The terminal device according to any one of claims 1)˜10), wherein thecontrol unit transmits the first resource information by using aphysical channel that is able to be commonly received by differentoperators.

(12)

The terminal device according to any one of claims 1)˜11), wherein in acase where the control unit receives second resource information whichindicates, among radio resources of which access rights are acquired byanother terminal device by performing carrier sense, a radio resourceavailable to another communication device other than the anotherterminal device, the control unit transmits a signal by using the radioresource available to the another communication device.

(13)

The terminal device according to claim 12), wherein a type of a signaltransmittable by using a radio resource available to the anothercommunication device is limited.

(14)

The terminal device according to claim 12) or 13), wherein the controlunit transmits a signal with transmission power equal to or less thantransmission power assumed in carrier sense performed when the anotherterminal device acquires an access right.

(15)

The terminal device according to any one of claims 12)˜14), wherein thecontrol unit transmits a signal by using resources available to theanother communication device in a case where a degree of similarity in acommunication environment with the another terminal device exceeds apredetermined value.

(16)

The terminal device according to claim 15), wherein the second resourceinformation includes information on a communication environment.

(17)

A base station device comprising:

a control unit configured to receive resource information whichindicates, among radio resources of which access rights are acquired bya terminal device by performing carrier sense, a resource available toanother communication device other than the terminal device from theterminal device and use the resource available to the anothercommunication device for communication.

(18)

The base station device according to claim 17), wherein the control unittransmits a signal on the basis of the resource information by using aradio resource available to the another communication device.

(19)

The base station device according to claim 17), wherein the control unittransmits a grant message giving an instruction on transmission of asignal in a radio resource available to the another communication deviceto another terminal device other than the terminal device on the basisof the resource information.

(20)

A method performed by a processor, comprising:

-   -   transmitting first resource information, which indicates a radio        resource available to another communication device among radio        resources of which access rights are acquired by performing        carrier sense, on an uplink or a sidelink.

REFERENCE SIGNS LIST

-   1 SYSTEM-   11 CELL-   12 CARRIER SENSE RANGE-   20 CORE NETWORK-   30 PDN-   100 BASE STATION DEVICE-   110 ANTENNA UNIT-   120 WIRELESS COMMUNICATION UNIT-   130 NETWORK COMMUNICATION UNIT-   140 STORAGE UNIT-   150 CONTROL UNIT-   151 ACCESS RIGHT SHARING UNIT-   153 COMMUNICATION PROCESSING UNIT-   200 TERMINAL DEVICE-   210 ANTENNA UNIT-   220 WIRELESS COMMUNICATION UNIT-   230 STORAGE UNIT-   240 CONTROL UNIT-   241 ACCESS RIGHT SHARING UNIT-   243 COMMUNICATION PROCESSING UNIT

1. A base station device, comprising: a radio transceiver; and controlcircuitry configured to: control the radio transceiver to receiveChannel Occupancy Time (COT) information on Physical Uplink SharedChannel (PUSCH) from a user equipment, wherein the COT information isinformation to share a COT between the base station device and the userequipment, and the COT information indicates each of: first informationthat indicates a start timing for the base station device to start theshare of the COT, second information that indicates a length of the COTduring which the base station device is able to share the COT, and thirdinformation that indicates a channel access priority class; and control,based on the COT information, the radio transceiver to transmit asignal.
 2. The base station device according to claim 1, wherein thecontrol circuitry is further configured to execute, based on the COTinformation, channel access without execution of carrier sensing.
 3. Thebase station device according to claim 2, wherein the first informationfurther indicates a number of slots, and the control circuitry isfurther configured to: add the number of slots to a slot number at whichthe COT information is received; and recognize a remaining duration ofthe COT based on the added number of slots.
 4. A user equipment,comprising: control circuitry configured to: control a radio transceiverof the user equipment to transmit Channel Occupancy Time (COT)information on Physical Uplink Shared Channel (PUSCH) to a base stationdevice, wherein the COT information is information to share a COTbetween the base station device and the user equipment, and the COTinformation indicates each of: first information that indicates a starttiming for the base station device to start the share of the COT, secondinformation that indicates a length of the COT during which the basestation device is able to share the COT, and third information thatindicates a channel access priority class; and control the radiotransceiver to receive a signal from the base station device, whereinthe control of the radio transceiver is based on the COT information. 5.The user equipment according to claim 4, wherein the base station deviceexecutes, based on the COT information, channel access without executionof carrier sensing.
 6. The user equipment according to claim 5, whereinthe first information further indicates a number of slots, and the basestation device further: adds the number of slots to a slot number atwhich the COT information is transmitted; and recognizes a remainingduration of the COT based on the added number of slots.
 7. Anon-transitory computer-readable medium having stored thereon,computer-executable instructions which, when executed by a controlcircuitry of a user equipment, cause the control circuitry to executeoperations, the operations comprising: controlling a radio transceiverof the user equipment to transmit Channel Occupancy Time (COT)information on Physical Uplink Shared Channel (PUSCH) to a base stationdevice, wherein the COT information is information to share a COTbetween the base station device and the user equipment, and the COTinformation indicates each of: first information that indicates a starttiming for the base station device to start the share of the COT, secondinformation that indicates a length of the COT during which the basestation device is able to share the COT, and third information thatindicates a channel access priority class; and controlling the radiotransceiver to receive a signal from the base station device, whereinthe control of the radio transceiver is based on the COT information. 8.The non-transitory computer-readable medium according to claim 7,wherein the base station device executes, based on the COT information,channel access without execution of carrier sensing.
 9. Thenon-transitory computer-readable medium according to claim 8, whereinthe first information further indicates a number of slots, and the basestation device further: adds the number of slots to a slot number atwhich the COT information is transmitted; and recognizes a remainingduration of the COT based on the added number of slots.
 10. A method,comprising: in a base station device: controlling a radio transceiver ofthe base station device to receive Channel Occupancy Time (COT)information on Physical Uplink Shared Channel (PUSCH) from a userequipment, wherein the COT information is information to share a COTbetween the base station device and the user equipment, and the COTinformation indicates each of: first information that indicates a starttiming for the base station device to start the share of the COT, secondinformation that indicates a length of the COT during which the basestation device is able to share the COT, and third information thatindicates a channel access priority class; and controlling, based on theCOT information, the radio transceiver to transmit a signal.
 11. Themethod according to claim 10, further comprising executing, based on theCOT information, channel access without execution of carrier sensing.12. The method according to claim 11, wherein the first informationfurther indicates a number of slots, the method further comprises:adding the number of slots to a slot number at which the COT informationis received; and recognizing a remaining duration of the COT based onthe added number of slots.
 13. A method, comprising: in a userequipment: controlling a radio transceiver of the user equipment totransmit Channel Occupancy Time (COT) information on Physical UplinkShared Channel (PUSCH) to a base station device, wherein the COTinformation is information to share a COT between the base stationdevice and the user equipment, and the COT information indicates eachof: first information that indicates a start timing for the base stationdevice to start the share of the COT, second information that indicatesa length of the COT during which the base station device is able toshare the COT, and third information that indicates a channel accesspriority class; and controlling the radio transceiver to receive asignal from the base station device, wherein the control of the radiotransceiver is based on the COT information.
 14. The method according toclaim 13, wherein the base station device executes, based on the COTinformation, channel access without execution of carrier sensing. 15.The method according to claim 14, wherein the first information furtherindicates a number of slots, and the base station device further: addsthe number of slots to a slot number at which the COT information istransmitted; and recognizes a remaining duration of the COT based on theadded number of slots.